Telegraph-key.



R. M. ALLEN.v

TELEGRAPH KEY. APPUcMloNrILEo MAY 29. |914.

Patented July 11,1916.

H l l .A IVF. ,MA WM MW. Hf y /p/A l/V//nessesf ENTTED STATES PATENTOEEi-CE.

ROY M. ALLEN, OE EAST ORANGE, NEW JERSEY, 'AssIGNOR RY MESNEASSIGNMENTS, TO WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATION OFNEW YORK.

TELEGRArH-KEY.

Specification of Letters Patent. i Patented uly v11, 191.6.

Application led May 29, 1914. Serial N o. 841,872.

. l To all whom t may concern:

i Keys, of which the following is a full, clear,

concise, and exact description'.

This invention relates to telegraph keys, and more particularly tosemi-automatic mechanical telegraph keys. In telegraph keys of thistype, which have been heretovfore produced, considerable trouble is eX-perienced on account of the production of what is termed split dots.Generally,

- when la dot is split into two or more sections by the key at thesending end, there results a distortion of the signal received at thedistant end, Which, as is generally known, means the reception of aletter different from that sent. Depending upon the speed of sending,the distortion may vresult in the reception of either more or less dotsthan were sent. If the speed of sending is slow, and a dot is split intotwo or more sections, the time that current is onthe line is generallyof sufficient duration to permit the operation of the receivingapparatus, thereby causing the reception of more dots than were sent,while if the Speed of sending is fast, the time current is on the lineis generally not of sufficient duration to permit rthe operation of thereceiving apparatus, thereby causing the reception of less dots thanwere sent.

It is the object of this invention, therefore, to produce a telegraphkey in the operation of which it is impossible to make split dots. v

This invention will be more fully understood by reference to thedrawingsshowing one embodiment thereof and wherein- I Figure 1 is a planView of a telegraph key; Fig. 2 is a side elevation` of the telegraphkey shown in Fig. 1; and Fig. 3 is a sectional view on line 3-3 of Fig.1.

' As shown in the drawings, the telegraph Akey comprises a base 5 havingan opening 6 therein over which there is placed a plate 7 secured to thebase 5 by means of screws 8, 8. A trunnion bracket 9 is mounted -uponthe plate 7. An operators L-shaped key lever 10, having insulatinglinger pieces 11, moves .from left to rig-ht and from right to left on avertical shaft 12 suitably mounted in upper and lower bearings in thebracket 9. An lend of the key leverlO is provided with a downwardlyextending portion 13, which, when the key lever 10 is moved from left toright, engages a pin 16 carried by one end of a lever 14 mountedon ashaft 15 suitably mounted in upper and lower bearings in the bracket 9.A flat vertical spring 20 is secured to the other end of lever 14and hasattached to its opposite end a vibrating rod or bar 21 carrying a weight22, which may -be slid back and forth thereon and held at any desiredpoint. A Spring member 24,

carrying at one end a contact 25, is secured I.

to the free end of and operates with the vibrating bar 21, a spacer 26being interposed between the spring member 24' and the bar 21. Acomparatively rigid backing leaf 27 is provided for the spring member24. The spring member 24 is mounted parallel to and alongsidethevibrating bar 21, and the contact 25 is carried in the plane ofvibration of the vibrating bar 21. The

spring member A24 is tensioned normally in the direction of thevibrating bar 21. In Order that the contact 25 may be adjusted and thatthe spring member 24 may normally rest just against the backing leaf 27,a screw 31 is adjustably mounted in the vibrating bar 21, the forwardend of the screw 31 being in engagement with said spring member.Normally, the lever 14 is held in a biased position against a stop pin28 carried by an arm 29 of the bracket 9 by means 56`adjustably mountedin an upwardly eX- support 40 and carries in one end a piece of leather4l or other suitable damping material. The free end of the spring 24 isnormally held at rest against a piece of rubber 42 Vor othersuitable`insulating material carried in one end of a screw 43 adjustably mountedin a support 44, the screw 43 passing through an opening 32 in thevibrating bar 21.

A second trunnion bracket 50 is mounted on the plate 7 but insulatedtherefrom by means of a strip 51 of mica or other suitable insulatingmaterial. A lever 52, carrying at one end a contact 53', is mounted on avertical shaft 54 suitably mounted in up- -per and lower bearings ortrunnion screws y(49 held in the bracket 50. The downwardly 4extendingportion 13 of the key lever 10, "when said key lever is moved from rightto left, engages the insulating tip 55 of a screw vtending portion 57 ofan intermediate lever 58 mounted on shoulders 59 formed on the trunnionscrews 49.

The expansion of a coiled spring 64, one

end of which is in engagement with an end of the contact-carrying lever52 and the other end with an adjustment screw 65 mounted in an arm 66 ofthe bracket 50, holds the contact-carrying lever 52 in a normally biasedposition against the end of an adjustment screw 67 carried in one end ofthe intermediate lever 58. The eX- pan'sion of the spring 64, throughthe medium of the contact-carrying lever 52 and the screw 67, also holdsthe intermediate `lever 58 in a normally biased position against a stoppin 68 carried by an arm 69 of the bracket 50.

70 and 71 represent terminals to which l the conductors of the telegraphcircuit may be attached. In order that the line circuit, to which thetelegraph key is connected, may be closed when the key is not in use, acircuit-closing lever 72 is pivoted at 74 on an extension 73 of thebracket 50 and is adapted to engage the Contact jaws 75 mounted on anextension 7 6 of the bracket 9.

When the key lever 10 is moved to the right from normal position, lever14 is moved away from the stop pin 28 and against the adjustably mountedstop screw 37, the vibrating bar 21 from the stop 41 'and the spring 24from the stop 42, whereby the bar 21 is permitted to vibrate, causingthe contact 25 to rapidly engage and disengage Contact 53 making aseries of dots.

When the key leverV 10 is moved to the left from normal position, theintermediate llever 58 is moved away from the stop pin 68, and throughthe screw 67 moves the contact-carrying lever 52, whereby the contact 53is brought into engagement with Contact 25 making a f dash.

- dot is only half completed, and then decreases gradually until thesecontacts disengage. The mounting of the contact 25 in the plane ofvibration of the vibrating bar 2l insures the movement of this contactin this plane only and without any torsional cliect upon the vibratingbar21, and prevents any secondary vibrations being set lup in themechanism. Since the contact 25 is subject to primary vibration only,and

'furthermore since the pressure between contacts 25 and 53 is greatestat the middle of the dot, there is no tendency for the key to produceso-called split dots.

What is claimed is: j c 1. A telegraph key comprising a contactmountedupon the free end of said vibrator the plane of vibration of saidvibrator, and

v a device for actuating said contact-carrying lever to produce dashesand said vibrator to produce dots.

2. A telegraph key comprising a contactcarrying lever, a vibrator havingan opening therein, a spring member mounted upon the free end of saidvibrator andparallel thereto, a contact carried on the free end of saidspring member and in the pla-ne of vibration of said vibrator, anadjustable stop pin for said contact passing throughy said opening, andmeans for actuating said contact-carrying lever to produce dashes andsaid vibrator to produce dots.

3. A telegraph key comprising a pivoted lever, a contact carriedthereby, a vibrator,

a leaf spring mounted on the free end of said vthereby intol engagementwith said other contact to produce dashes.

4. A telegraph key comprising a pivoted lever, a contact carriedthereby, a vibrator having an opening therein, a leaf spring mountedupon the free end of said vibrator and parallel thereto, a contactcarried on the free end of said leaf spring and in the plane ofvibration of said vibrator, a floating key lever adapted to be moved inone direction 'carrying lever, a vibrator, a spring member tain saidContact stationary when producing dashes.

In Witness whereof, I hereunto subscribe my name this 28 day of May, A.D. 1914.

ROY M. ALLEN.

to actuate said vibrator to cause engagement of said contacts to producedots and in the other direction to actuate said lever to move thecontact carried thereby into engagement 5 With said other contact t0produce dashes,

and an adjustable stop pin passing through Witnesses: the opening insaid vibrator and into en- K. L. STAHL, gagement with the vibratorcontact to main- R. E. OLSON.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

